Influence of interstrand current redistribution on acceleration of quench propagation in eight-strand Rutherford cables

In order to study the relationship between quench propagation velocity and current redistribution during a quench, heater quench tests were performed. The cable used was eight-strand Rutherford cable coated with Sn-5Ag, which was subjected to a uniform magnetic field of 4 T. The quench process was measured by using voltage taps and sets of pickup coils. The authors found that, over a certain transport current, the quench propagation velocity accelerated as the normal zone propagated. The relationship between the quench propagation velocity and the current redistribution is discussed.